Electrical connectors are widely used in the automotive industry to detachably interconnect and provide electrical continuity between wiring harnesses and various other electrical components. A representative electrical connector comprises a plurality of electrical terminals or contacts held by a nonconductive connector body, with the body adapted to physically engage a mating connector to place the terminals in electrical contact with corresponding terminals of the mating connector. It is common for such mating pairs of connectors to include some form of locking means whereby they may be secured in engagement with one another once in a properly mated relationship. Such locking means serve to ensure that the connector pairs stay positively mated during use and are not inadvertently disconnected by, for example, vibration or incidental contact with other objects during use or maintenance.
It is sometimes necessary, for example in the course of the repair or replacement of a defective component, to intentionally disconnect an electrical connector from its mating connector. For this reason it is necessary to provide a locking means which may be disengaged or otherwise overcome by a worker when desired, and in the interests of speed and simplicity it is advantageous if this can be accomplished without the use of any tools. Hence, many prior electrical connector designs have featured locking means that are biased, as by a spring or the equivalent, to lockingly engage the mating connector when the two connectors are fully mated, and that may be unlocked by hand, i.e. by squeezing or pressing on the connector or some portion thereof with one's fingers to overcome the biasing force, to permit disengagement of the connectors.
It should be apparent that in the design of lockable connectors a trade-off exists in regards to ease of intentional unlocking by a worker on the one hand and resistance to inadvertent unlocking on the other. To be easily manually unlocked by a worker, the portion of the connector that is actuated should be (a) relatively large with respect to the size of the average worker's fingertips, (b) located and configured to provide unobstructed access by the worker, and (c) actuatable with a minimum of effort. These same features, however, increase the likelihood that the connector may be inadvertently unlocked during operational use or shipping.
One prior lockable connector design features a locking arm attached at one end to the exterior surface of the connector and extending in a cantilever fashion substantially parallel with the surface. In its normally biased condition the locking arm, due to its inherent stiffness or to a separate spring, stands away from the connector surface by a small amount. In this position, detent means on the locking arm is in locked engagement with cooperating detent means on the mating connector when the two connectors are properly joined. To release the detent means of the two connectors from locked engagement with one another the locking arm is depressed, forcing it toward the connector surface. Although quite easily and quickly releasable by a worker, it is also possible for such a locking arm to be depressed inadvertently in its operating environment where other objects may press or rub against it.
In order to decrease the likelihood of the locking arm being inadvertently depressed, the connector described above has been modified to include small fins or blocks that extend from the connector surface in close proximity to either side of the free end of the locking arm. These side guards extend upward at least to the level of the highest point of the locking arm, thereby obstructing access to the arm so that an object must fit between the side guards in order to depress the locking arm. For ease of actuation by a worker, the side guards must be spaced far enough apart for an average sized adult worker's fingertip to fit therebetween and press down on the locking arm. Spacing the side guards widely enough for comfortable actuation of the locking arm by a worker, though, can make the locking arm too susceptible to inadvertent actuation.
It has also been found that an electrical connector featuring a locking arm as described above may be damaged during shipping. Electrical connectors are commonly assembled as part of a wiring harness, and one or more harnesses are then packed loosely in a carton for shipping to a location where subsequent component assembly takes place. The vibration and jostling that occurs during shipping and handling of the carton can cause the wires that make up the harnesses to work their way underneath the locking arm, into the gap between the connector body and the arm. If a connector becomes snagged on the harness wiring in this fashion, the locking arm may break off of the connector or be otherwise damaged when the harnesses are pulled out of the carton.
Therefore, it would be desirable to provide a means by which the locking arm of a lockable connector as described above is guarded against being inadvertently depressed and also against snagging on wires or other objects.